1. Field of the Invention
This invention relates generally to improvements in agricultural implements and more particularly to spring-biased disc gang section for use with disc implements of either tandem or offset design.
The prior art disc constructions have exclusively mounted the rotating blades to the disc frame in a rigid manner. Therefore, when an individual disc blade strikes a solid object, such as a large rock or the like, the rigidly mounted disc blade will not yield and thus will become damaged. Often times, the components of the disc machinery are damaged as well. In accordance with the present invention, the disc blades are spring-biased and pivotally mounted as a unit onto the disc frame so as to enable the discs to yield upon one or more discs striking an object and return to the normal working position once the object has been passed without the excessive damage which has plagued disc machinery since the beginning of the time such machinery has been used for working the soil.
2. Disclosure Statement
It has been known to provide soil-conditioning implements with mountings which permit the implements to pass over obstructions, such as rocks, without damage to the implements or surrounding component parts of the machinery. U.S. Pat. No. 3,451, 489, issued June 24, 1969, to Sullivan, mentions that prior art spring-loaded rolling coulter constructions were known, but had not been entirely successful, since the prior art devices generally employed helical compression springs to normally bias the rolling coulter into a ground-working position. The patentee states that the employment of helical compression springs is not desirable since the springs must be of fairly large size to have the desired initial preload and that the relatively large size causes trash to build up upon the coulter assembly. The Sullivan patent replaced the helical compression springs of the prior art with Belleville washers. U.S. Pat. No. 3,700,037, issued Oct. 24, 1972, to Hentrich et al, also attempted to improve the spring-biasing of coulters on moldboard plows and, in particular, attempted to improve upon the structure patented by Sullivan mentioned above. Hentrich et al discloses an improved cushion mounting for coulters which can use either spring cushions or hydraulic cushions. In each of the above-mentioned patents, the cushion means for the coulters are situated in the proximity of the rolling coulter and it is understandable that Sullivan would be concerned about the build up of trash on the coulter assembly affecting the operation of the assembly. As will be more fully described, in the present invention the springs are positioned above the disc frame and are spaced at a considerable distance from the rotating discs and soil. Another important difference between prior art spring-loaded rolling coulters and the present invention concerns the fact that in each of the coulters the springs are associated with the individual rolling coulters, while in the present invention, a disc section comprising a plurality of blades is spring-biased as a unit such that upon any one of the rotating blades of the section striking an object, the entire section is pivoted to pass over obstructions which may be encountered.
The concept of utilizing spring-biasing of soil-treating implements in order to cushion the force between the implement and the ground are not limited to rolling coulters, but have been disclosed for use in plows as disclosed in U.S. Pat. Nos. 3,202,223, issued Aug. 24, 1965, to Fulton, 3,606,928, issued Sept. 21, 1971, to Quanbeck and 3,782,481, issued Jan. 1, 1974, also to Quanbeck. Again, each of these patents disclose the addition of springs onto each plow and not to a section of individual plows. Spring biasing the blades of a disc has heretofore been unknown.